I currently have a athlon64x2 processor on a nforce4 based motherboard. All of my current gentoo installation has been compiled for this, with the -march flag set to athlon64.

I have ordered the components to upgrade my computer to a phenom ii based system on an nvidia 750a based motherboard.
Presumably, the first stage would be to use the minimal install cd to rebuild the kernel.
I will need to change the -march flag to barcelona to enable the new processors features, will I then need to remerge world before it will run properly on the new system?

You won't have a problem with that. It's a good time to set -march=native instead. Strictly speaking, you don't need to recompile anything unless you are paranoid about that. The system will eventually catch up if you use "native"._________________Gentoo Handbook | My website

yeah I would second the -march=native usage as that will automagically utilize the correct optimizations for your cpu. You will only need to recompile kernel if your new motherboard requires different drivers for things like LAN, Sound, etc..._________________Increasingly becoming a 2 channel audio nut!

please, if you value your money, stay away from nvidia based chipset mb, they are pure crap._________________Only two things are infinite, the universe and human stupidity and I'm not sure about the former - Albert Einstein
ProjectFootball

yeah I would second the -march=native usage as that will automagically utilize the correct optimizations for your cpu. You will only need to recompile kernel if your new motherboard requires different drivers for things like LAN, Sound, etc...

Yep, they will all change for the new chipset, so I think that I wlll need to use the minimal cd to recompile the kernel.

DaggyStyle wrote:

please, if you value your money, stay away from nvidia based chipset mb, they are pure crap.

Care to provide any evidence for this? Without any, this statement is a little weak.
Besides, having already paid for my new motherboard, it is a little late to change.

Care to provide any evidence for this? Without any, this statement is a little weak.
Besides, having already paid for my new motherboard, it is a little late to change.

check tomshardware's forums, ask there... I won't answer you there I promise

my previous hp laptop has nvidia chipset, the mb was replaced 6 times in 3 three years, now after the warranty expired guess what happened...

Hmm, well given that I have been using my current motherbaord (nforce4 chipset) for over 2 years without problems, and I have just bought another nvidia based motherboard, I would rather not tempt fate by looking up other peoples crashes beforehand.

Care to provide any evidence for this? Without any, this statement is a little weak.
Besides, having already paid for my new motherboard, it is a little late to change.

check tomshardware's forums, ask there... I won't answer you there I promise

my previous hp laptop has nvidia chipset, the mb was replaced 6 times in 3 three years, now after the warranty expired guess what happened...

Hmm, well given that I have been using my current motherbaord (nforce4 chipset) for over 2 years without problems, and I have just bought another nvidia based motherboard, I would rather not tempt fate by looking up other peoples crashes beforehand.

Anyway, this is slightly off the threads topic.

it's your call, I've just wanted to help out._________________Only two things are infinite, the universe and human stupidity and I'm not sure about the former - Albert Einstein
ProjectFootball

Ok. Upgrade carried out.
Kernel rebuilt from minimal cd.
This enabled booting into old system, where I then changed to march=amdfam10 (not native, see below)
I then did a rebuild of system + nvidia-drivers.

Now I am back to a working system, and am carrying out a full world rebuild.

NB: I chose not to use native because I use distcc and the gcc manual stated that using native with distcc was known to cause problems particularly when compiling across different architectures (which I do, since I compile with some core2s).

Well, I see my advice to build new kernel for your new hardware while still running on old hardware wasn't taken. Would have saved hassle with CD.
I switched from AMD to Intel once, my new kernel was ready while the new hardware was still in mail._________________Please learn how to denote units correctly!

Well, I see my advice to build new kernel for your new hardware while still running on old hardware wasn't taken. Would have saved hassle with CD.
I switched from AMD to Intel once, my new kernel was ready while the new hardware was still in mail.

Its good to switched from AMD to Intel once??? may be just due to the name of intel? Do there are best then this one?> Apple ?_________________hi everybody, I enjoy reading, walking, outdoor team sports, alternative medicine and listening to music.
bowtrol

I currently have a athlon64x2 processor on a nforce4 based motherboard. All of my current gentoo installation has been compiled for this, with the -march flag set to athlon64.

I have ordered the components to upgrade my computer to a phenom ii based system on an nvidia 750a based motherboard.
Presumably, the first stage would be to use the minimal install cd to rebuild the kernel.
I will need to change the -march flag to barcelona to enable the new processors features, will I then need to remerge world before it will run properly on the new system?

Thanks.
Ali

You're going to see basically no difference in performance.

Just change /etc/make.conf and packages will be recompiled with the new flags as you update.

richard.scott wrote:

If your not changing down the model range, or changing make i.e. Intel, then you should be ok.... you'll soon know if it won't work as it won't boot

Once its booted, you can change your flangs and then emerge -eav system, emerge -eav world a few times like you would if you'd updated GCC.

Rich.
p.s. the only thing you can't do with a system rebuild like this is go from 32bit -> 64bit... that needs a total re-install.

Ugh. So much misinformation.

When you `emerge gcc`it rebuilds itself. Let me say that another way.

Running `emerge gcc` bootstraps gcc, and produces an executable called xgcc. So say you have gcc-4.3.4 installed, and you're upgrading to 4.4.2. gcc-4.3.4 compiles the gcc-4.4.2 sources and produces `xgcc'. Then xgcc (again, built from the 4.4.2 sources) builds gcc-4.4.2 and installs it on your system.

I can't imagine how much time you've wasted rebuilding your system multiple times after a gcc upgrade.

I can't imagine how much time you've wasted rebuilding your system multiple times after a gcc upgrade.

I thought the point of emerge -e system && emerge -e world after a gcc update was so that everything was recompiled using the new gcc version. The documentation makes it sound like there would be issues if you don't.

Quote:

To be completely safe that your system is in a sane state, you must rebuild the toolchain and then world to make use of the new compiler.